Morphometrics, growth characteristics, and phylogenetic implications of Halysites catenularius (Tabulata, Silurian, Estonia)

• Published in: Journal of Paleontology
• Main Authors: Liang, Kun, Elias, Robert J., Lee, Dong-Jin
• Format: Report
• Language: English
• Published: CAMBRIDGE UNIV PRESS 2019
• Subjects: LIFE-HISTORY STRATEGIES; UPPER ORDOVICIAN; LOPHELIA-PERTUSA; SOUTHERN MANITOBA; CATENIPORA TABULATA; CORALLITE INCREASE; PATTERNS; STROMATOPOROIDS; SCLERACTINIA; WENLOCK; Paleontology; Lophelia pertusa
• Online Access: http://ir.nigpas.ac.cn/handle/332004/15010; https://doi.org/10.1017/jpa.2018.73

Based on multivariate morphometric analysis, Halysites catenularius is identified from the Rumba Formation (Telychian) and Jaagarahu Formation (Sheinwoodian) of Estonia; H. priscus is confirmed as a junior synonym. Halysites catenularius, H. junior, and H. senior are shown to be closely related; H. catenularius is morphologically intermediate. Cyclomorphism in H. catenularius, recorded by fluctuations of corallite tabularial area, indicates an average annual growth rate of 6.0 mm, which is typical for halysitids. Tubules in H. catenularius, generated from small intramural openings between adjacent corallites, were involved in two types of interstitial increase. The intramural openings, three types of lateral increase, temporary agglutinated patches of corallites, and axial increase documented in H. catenularius resemble features in some species of Catenipora. These similarities are consistent with the interpretation that Halysites evolved from Catenipora. Evaluation of the possibility that both genera are polyphyletic will require further detailed analysis of additional species.